Ultrasonic liquid flow control apparatus and method

ABSTRACT

An ultrasonic apparatus and method for regulating the flow of a pressurized liquid through an orifice by applying ultrasonic energy to a portion of the pressurized liquid. The apparatus includes a die housing which defines a chamber adapted to receive a pressurized liquid and a means for applying ultrasonic energy to a portion of the pressurized liquid. The die housing further includes an inlet adapted to supply the chamber with the pressurized liquid, and an exit orifice defined by the walls of a die tip. The exit orifice is adapted to receive the pressurized liquid from the chamber and pass the liquid out of the die housing. When the means for applying ultrasonic energy is excited, it applies ultrasonic energy to the pressurized liquid without applying ultrasonic energy to the die tip and modifies the flow rate of the pressurized liquid the exit orifice. The method involves supplying a pressurized liquid to the foregoing apparatus, applying ultrasonic energy to the pressurized liquid but not the die tip while the exit orifice receives pressurized liquid from the chamber to modify the flow rate of the pressurized liquid through the exit orifice, and passing the pressurized liquid out of the exit orifice in the die tip at the modified flow rate.

BACKGROUND OF THE INVENTION

The present invention relates to an apparatus for controlling the flowof a liquid. The present invention also relates to a method ofcontrolling the flow of a liquid.

SUMMARY OF THE INVENTION

The present invention provides an apparatus and a method for regulatingthe flow rate of a pressurized liquid through an orifice by applyingultrasonic energy to a portion of the pressurized liquid.

The apparatus includes a die housing which defines a chamber adapted toreceive a pressurized liquid and a means for applying ultrasonic energyto a portion of the pressurized liquid. The die housing includes achamber adapted to receive the pressurized liquid, an inlet adapted tosupply the chamber with the pressurized liquid, and an exit orifice (ora plurality of exit orifices) defined by the walls of a die tip, theexit orifice being adapted to receive the pressurized liquid from thechamber and pass the liquid out of the die housing. Generally speaking,the means for applying ultrasonic energy is located within the chamber.For example, the means for applying ultrasonic energy may be an immersedultrasonic horn. According to the invention, the means for applyingultrasonic energy is located within the chamber in a manner such thatsubstantially no ultrasonic energy is applied to the die tip (i.e., thewalls of the die tip defining the exit orifice).

In one embodiment of the present invention, the die housing may have afirst end and a second end. One end of the die housing forms a die tiphaving walls that define an exit orifice which is adapted to receive apressurized liquid from the chamber and pass the pressurized liquidalong a first axis. The means for applying ultrasonic energy to aportion of the pressurized liquid is an ultrasonic horn having a firstend and a second end. The horn is adapted, upon excitation by ultrasonicenergy, to have a node and a longitudinal mechanical excitation axis.The horn is located in the second end of the die housing in a mannersuch that the first end of the horn is located outside of the diehousing and the second end is located inside the die housing, within thechamber, and is in close proximity to the exit orifice.

The longitudinal excitation axis of the ultrasonic horn desirably willbe substantially parallel with the first axis. Furthermore, the secondend of the horn desirably will have a cross-sectional area approximatelythe same as or greater than a minimum area which encompasses all exitorifices in the die housing. Upon excitation by ultrasonic energy, theultrasonic horn is adapted to apply ultrasonic energy to the pressurizedliquid within the chamber (defined by the die housing) but not to thedie tip which has walls that define the exit orifice.

The present invention contemplates the use of an ultrasonic horn havinga vibrator means coupled to the first end of the horn. The vibratormeans may be a piezoelectric transducer or a magnetostrictivetransducer. The transducer may be coupled directly to the horn or bymeans of an elongated waveguide. The elongated waveguide may have anydesired input:output mechanical excitation ratio, although ratios of 1:1and 1:1.5 are typical for many applications. The ultrasonic energytypically will have a frequency of from about 15 kHz to about 500 kHz,although other frequencies are contemplated.

In an embodiment of the present invention, the ultrasonic horn may becomposed of a magnetostrictive material. The horn may be surrounded by acoil (which may be immersed in the liquid) capable of inducing a signalinto the magnetostrictive material causing it to vibrate at ultrasonicfrequencies. In such cases, the ultrasonic horn may be simultaneouslythe transducer and the means for applying ultrasonic energy to themulti-component liquid.

In an aspect of the present invention, the exit orifice may have adiameter of less than about 0.1 inch (2.54 mm). For example, the exitorifice may have a diameter of from about 0.0001 to about 0.1 inch(0.00254 to 2.54 mm) As a further example, the exit orifice may have adiameter of from about 0.001 to about 0.01 inch (0.0254 to 0.254 mm).

According to the invention, the exit orifice may be a single exitorifice or a plurality of exit orifices. The exit orifice may be an exitcapillary. The exit capillary may have a length to diameter ratio (L/Dratio) of ranging from about 4:1 to about 10:1. Of course, the exitcapillary may have a L/D ratio of less than 4:1 or greater than 10:1.

The present invention encompasses a method of regulating the flow of apressurized liquid through an orifice. The method involves supplying apressurized liquid to the apparatus described above, exciting the meansfor applying ultrasonic energy with ultrasonic energy while the exitorifice receives pressurized liquid from the chamber (without applyingultrasonic energy to the die tip) to modify the flow rate of thepressurized liquid through the exit orifice, and passing the pressurizedliquid out of the exit orifice in the die tip at the modified flow rate.

According to the present invention, the flow rate of the pressurizedliquid may be at least about 25 percent greater than the flow rate of anidentical pressurized liquid out of an identical die housing through anidentical exit orifice in the absence of excitation by ultrasonicenergy. For example, the flow rate of the pressurized liquid is at leastabout 75 percent greater. As another example, the flow rate of thepressurized liquid is at least about 200 percent greater.

Generally speaking, regulating the flow rate of the pressurized liquidmay be achieved without significant elevation in the temperature of thepressurized liquid and/or without significant elevation in the suppliedpressure of the pressurized liquid. The present invention contemplatesthat regulating the flow rate of the pressurized liquid may be achievedwithout degrading the pressurized liquid over the course of many cycles.The apparatus and method of the present invention may be used toregulate the flow rates of liquid components being added to a processstream of other liquid components such as, for example, chemicals,foods, paints, effluents and petroleum products.

The apparatus and method of the present invention may also be used toprovide flow control in both open and closed circuit hydraulic systemsin a variety of settings including, but not limited to, automotive,construction, industrial, agricultural and robotic.

It is also contemplated that the apparatus and method of the presentinvention may be used to control the phase change rate of liquidrefrigerants by utilizing equipment such as, for example, ultrasonicallycontrolled thermal expansion valves. The apparatus and method of thepresent invention can also provide advantages in the mass transfer andcontainer filling operations for a variety of food products, especiallyfood products that tend to be viscous.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagrammatic cross-sectional representation of oneembodiment of the apparatus of the present invention.

FIGS. 2 and 9 are illustrations of exemplary experimental set-ups torecycle liquid.

FIGS. 3-8 and 10-16 are illustrations of exemplary analyses of controland recycled liquids.

FIG. 17 is a diagrammatic cross-sectional representation of anotherembodiment of the apparatus of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

As used herein, the term "liquid" refers to an amorphous(noncrystalline) form of matter intermediate between gases and solids,in which the molecules are much more highly concentrated than in gases,but much less concentrated than in solids. A liquid may have a singlecomponent or may be made of multiple components. The components may beother liquids, solid and/or gases. For example, Characteristic ofliquids is their ability to flow as a result of an applied force.Liquids that flow immediately upon application of force and for whichthe rate of flow is directly proportional to the force applied aregenerally referred to as Newtonian liquids. Some liquids have abnormalflow response when force is applied and exhibit non-Newtonian flowproperties.

As used herein, the terms "thermoplastic material" and "thermoplasticpolymer" refer to a polymer that softens when exposed to heat andreturns to a relatively hardened condition when cooled to roomtemperature. Natural substances which exhibit this behavior are cruderubber and a number of waxes. Other exemplary thermoplastic materialsinclude, without limitation, polyvinyl chloride, polyesters, nylons,polyfluorocarbons, polyolefins (including polypropylene, polyethyene,linear low density polyethylene, etc.), polyurethane, polystyrene,polypropylene, polyvinyl alcohol, caprolactams, and acrylic resins.

As used herein, the term "node" means the point on the longitudinalexcitation axis of the ultrasonic horn at which no longitudinal motionof the horn occurs upon excitation by ultrasonic energy. The nodesometimes is referred in the art, as well as in this specification, asthe nodal point.

The term "close proximity" is used herein in a qualitative sense only.That is, the term is used to mean that the means for applying ultrasonicenergy is sufficiently close to the exit orifice (e.g., extrusionorifice) to apply the ultrasonic energy primarily to the liquid (e.g.,molten thermoplastic polymer) passing into the exit orifice (e.g.,extrusion orifice). The term is not used in the sense of definingspecific distances from the extrusion orifice.

As used herein, the term "consisting essentially of" does not excludethe presence of additional materials which do not significantly affectthe desired characteristics of a given composition or product. Exemplarymaterials of this sort would include, without limitation, pigments,antioxidants, stabilizers, surfactants, waxes, flow promoters, solvents,particulates and materials added to enhance processability of thecomposition.

Generally speaking, the apparatus of the present invention includes adie housing and a means for applying ultrasonic energy to a portion of apressurized liquid (e.g., a molten thermoplastic polymers, hydrocarbonoils, water, slurries, suspensions or the like). The die housing definesa chamber adapted to receive the pressurized liquid, an inlet (e.g.,inlet orifice) adapted to supply the chamber with the pressurizedliquid, and an exit orifice (e.g., extrusion orifice) adapted to receivethe pressurized liquid from the chamber and pass the liquid out of theexit orifice of the die housing. The means for applying ultrasonicenergy is located within the chamber. For example, the means forapplying ultrasonic energy can be located partially within the chamberor the means for applying ultrasonic energy can be located entirelywithin the chamber.

Referring now to FIG. 1, there is shown, not necessarily to scale, andexemplary apparatus for increasing the flow rate of a pressurized liquidthrough an orifice. The apparatus 100 includes a die housing 102 whichdefines a chamber 104 adapted to receive a pressurized liquid (e.g.,oil, water, molten thermoplastic polymer, syrup or the like). The diehousing 102 has a first end 106 and a second end 108. The die housing102 also has an inlet 110 (e.g., inlet orifice) adapted to supply thechamber 104 with the pressurized liquid. An exit orifice 112 (which mayalso be referred to as an extrusion orifice) is located in the first end106 of the die housing 102; it is adapted to receive the pressurizedliquid from the chamber 104 and pass the liquid out of the die housing102 along a first axis 114. An ultrasonic horn 116 is located in thesecond end 108 of the die housing 102. The ultrasonic horn has a firstend 118 and a second end 120. The horn 116 is located in the second end108 of the die housing 102 in a manner such that the first end 118 ofthe horn 116 is located outside of the die housing 102 and the secondend 120 of the horn 116 is located inside the die housing 102, withinthe chamber 104, and is in close proximity to the exit orifice 112. Thehorn 116 is adapted, upon excitation by ultrasonic energy, to have anodal point 122 and a longitudinal mechanical excitation axis 124.Desirably, the first axis 114 and the mechanical excitation axis 124will be substantially parallel. More desirably, the first axis 114 andthe mechanical excitation axis 124 will substantially coincide, as shownin FIG. 1.

The size and shape of an apparatus 400 of the present invention can varywidely, depending, at least in part, on the number and arrangement ofexit orifices (e.g., extrusion orifices) and the operating frequency ofthe means for applying ultrasonic energy. For example, the die housingmay be cylindrical, rectangular, or any other shape. Moreover, the diehousing may have a single exit orifice or a plurality 412 of exitorifices. The plurality 412 of exit orifices may be arranged in apattern, including but not limited to, a linear or a circular pattern.

The means for applying ultrasonic energy is located within the chamber,typically at least partially surrounded by the pressurized liquid. Suchmeans is adapted to apply the ultrasonic energy to the pressurizedliquid as it passes into the exit orifice. Stated differently, suchmeans is adapted to apply ultrasonic energy to a portion of thepressurized liquid in the vicinity of each exit orifice. Such means maybe located completely or partially within the chamber.

When the means for applying ultrasonic energy is an ultrasonic horn, thehorn conveniently extends through the die housing, such as through thefirst end of the housing as identified in FIG. 1. However, the presentinvention comprehends other configurations. For example, the horn mayextend through a wall of the die housing, rather than through an end.Moreover, neither the first axis nor the longitudinal excitation axis ofthe horn need to be vertical. If desired, the longitudinal mechanicalexcitation axis of the horn may be at an angle to the first axis.Nevertheless, the longitudinal mechanical excitation axis of theultrasonic horn desirably will be substantially parallel with the firstaxis. More desirably, the longitudinal mechanical excitation axis of theultrasonic horn desirably and the first axis will substantiallycoincide, as shown in FIG. 1.

If desired, more than one means for applying ultrasonic energy may belocated within the chamber defined by the die housing. Moreover, asingle means may apply ultrasonic energy to the portion of thepressurized liquid which is in the vicinity of one or more exitorifices.

According to the present invention, the ultrasonic horn may be composedof a magnetostrictive material. The horn may be surrounded by a coil(which may be immersed in the liquid) capable of inducing a signal intothe magnetostrictive material causing it to vibrate at ultrasonicfrequencies. In such cases, the ultrasonic horn can simultaneously bethe transducer and the means for applying ultrasonic energy to themulti-component liquid. The magnetostrictive horn may also act as apositive flow shut-off valve (as in a solenoid valve) by superimposing adirect current (DC) signal on the horn's induction coil thus causing thehorn to move against the orifice opening to shut-off the liquid flow.Liquid flow can be resumed by removing the DC signal and allowing someresilient piece (e.g., a spring) to push the horn back as in a solenoidvalve. That is, the apparatus may be configured so a DC signal on themagnetostrictive horn's induction coil causes the horn to shut-off theliquid flow and absence of the signal fully turns on the liquid flow.The DC signal may be superimposed on the magnetostrictive horn'sinduction coil separately or simultaneously with the signal to induceultrasonic vibration.

The application of ultrasonic energy to a plurality of exit orifices maybe accomplished by a variety of methods. For example, with referenceagain to the use of an ultrasonic horn, the second end of the horn mayhave a cross-sectional area which is sufficiently large so as to applyultrasonic energy to the portion of the pressurized liquid which is inthe vicinity of all of the exit orifices in the die housing. In suchcase, the second end of the ultrasonic horn desirably will have across-sectional area approximately the same as or greater than a minimumarea which encompasses all exit orifices in the die housing (i.e., aminimum area which is the same as or greater than the sum of the areasof the exit orifices in the die housing originating in the samechamber). Alternatively, the second end of the horn may have a pluralityof protrusions, or tips, equal in number to the number of exit orifices.In this instance, the cross-sectional area of each protrusion or tipdesirably will be approximately the same as or less than thecross-sectional area of the exit orifice with which the protrusion ortip is in close proximity.

The planar relationship between the second end of the ultrasonic hornand an array of exit orifices may also be shaped (e.g., parabolically,hemispherically, or provided with a shallow curvature or angle) toincrease the flow control range.

As already noted, the term "close proximity" is used herein to mean thatthe means for applying ultrasonic energy is sufficiently close to theexit orifice to apply the ultrasonic energy primarily to the pressurizedliquid passing into the exit orifice. The actual distance of the meansfor applying ultrasonic energy from the exit orifice in any givensituation will depend upon a number of factors, some of which are theflow rate of the pressurized liquid (e.g., the melt flow rate of amolten thermoplastic polymer or the viscosity of a liquid), thecross-sectional area of the end of the means for applying the ultrasonicenergy relative to the cross-sectional area of the exit orifice, thefrequency of the ultrasonic energy, the gain of the means for applyingthe ultrasonic energy (e.g., the magnitude of the longitudinalmechanical excitation of the means for applying ultrasonic energy), thetemperature of the pressurized liquid, and the rate at which the liquidpasses out of the exit orifice.

In general, the distance of the means for applying ultrasonic energyfrom the exit orifice in a given situation may be determined readily byone having ordinary skill in the art without undue experimentation. Inpractice, such distance will be in the range of from about 0.002 inch(about 0.05 mm) to about 1.3 inches (about 33 mm), although greaterdistances can be employed. Such distance determines the extent to whichultrasonic energy is applied to the pressurized liquid other than thatwhich is about to enter the exit orifice; i.e., the greater thedistance, the greater the amount of pressurized liquid which issubjected to ultrasonic energy. Consequently, shorter distancesgenerally are desired in order to minimize degradation of thepressurized liquid and other adverse effects which may result fromexposure of the liquid to the ultrasonic energy.

One advantage of the apparatus of the present invention is that it isself-cleaning. That is, the combination of supplied pressure and forcesgenerated by ultrasonically exciting the means for supplying ultrasonicenergy to the pressurized liquid (without applying ultrasonic energydirectly to the orifice) can remove obstructions that appear to blockthe exit orifice (e.g., extrusion orifice). According to the invention,the exit orifice is adapted to be self-cleaning when the means forapplying ultrasonic energy is excited with ultrasonic energy (withoutapplying ultrasonic energy directly to the orifice) while the exitorifice receives pressurized liquid from the chamber and passes theliquid out of the die housing. Desirably, the means for applyingultrasonic energy is an immersed ultrasonic horn having a longitudinalmechanical excitation axis and in which the end of the horn located inthe die housing nearest the orifice is in close proximity to the exitorifice but does not apply ultrasonic energy directly to the exitorifice.

It is contemplated that the apparatus and method of the presentinvention has a very wide variety of applications where it is desirableto regulate the flow of a pressurized liquid through an orifice. Forexample, the apparatus and method may be used in fuel injectors forliquid-fueled combustors. Exemplary combustors include, but are notlimited to, boilers, kilns, industrial and domestic furnaces,incinerators. Many of these combustors use heavy liquid fuels that maybe advantageously controlled and handled by the apparatus and method ofthe present invention.

The apparatus and method of the present invention can be used to provideflow control in both open and closed circuit hydraulic systems.Exemplary applications include, but are not limited to, automotivetransmissions, power steering, shock absorbers and anti-lock brakingsystems; construction and agricultural equipment hydraulic systems anddrives; industrial process control equipment, fluidic amplifiers andswitches; and robotic hydraulic systems including, but not limited to,systems designed to provide precise pressure control via bleed-off,stepless velocity changes in driven components and shockless motionstop.

Flow enhancement and flow control of viscous liquids present otherapplications for the apparatus and method of the present invention. Forexample, the present invention may be used to control and enhance theflow of molten bitumens, molten metals, molten glasses, viscous paints,hot melt adhesives, syrups, heavy oils, emulsions, slurries andsuspensions and the like.

It is also contemplated that the apparatus and method of the presentinvention may be used to control the phase change rate of liquidrefrigerants by utilizing equipment such as, for example, ultrasonicallycontrolled thermal expansion valves.

The apparatus and method of the present invention can also provideadvantages in the mass transfer and/or container filling operations fora variety of food products, especially food products that tend to beviscous. For example, it is contemplated that the present invention maybe used in the simultaneous process and fill operations of food productemulsions including, but not limited to, mayonnaise, salad dressing,spreads or the like.

An embodiment of the present invention relates to an ultrasonicapparatus for regulating the flow of pressurized liquid through anorifice in which the apparatus is composed of a die housing, amagnetostrictive ultrasonic horn surrounded by an induction coil capableof inducing ultrasonic vibration in the horn, and a means forsuperimposing a direct current signal on the induction coil so that theultrasonic horn moves to a position within the chamber to modify theflow rate of the pressurized liquid. For example, the apparatus may becomposed of a die housing defining a chamber adapted to receive apressurized liquid; an inlet adapted to supply the chamber with thepressurized liquid; and an exit orifice defined by the walls of a dietip, the exit orifice being adapted to receive the pressurized liquidfrom the chamber and pass the liquid out of the die housing.

An ultrasonic horn is located within the chamber, the horn beingcomposed of a magnetostrictive material and surrounded by an inductioncoil capable of inducing a signal into the magnetostrictive materialcausing it to vibrate at ultrasonic frequencies to apply ultrasonicenergy to a portion of the pressurized liquid within the chamber withoutapplying ultrasonic energy to the die tip.

The apparatus also includes a means for superimposing a direct currentsignal on the induction coil so that the ultrasonic horn moves to aposition within the chamber to modify the flow rate of the pressurizedliquid. For example, the direct current signal can cause the ultrasonichorn to move to a position that shuts-off the liquid flow and move toanother position to turn on the liquid flow when the direct currentsignal is removed. Thus, during operation of the apparatus the flow rateof pressurized liquid through the exit orifice modified when directcurrent signal is applied.

Another embodiment of the present invention relates to a method ofregulating the flow of pressurized liquid through an orifice. The methodis composed of the steps of supplying a pressurized liquid to a dieassembly described above. That is, a die assembly composed of a diehousing, a magnetostrictive ultrasonic horn surrounded by an inductioncoil capable of inducing ultrasonic vibration in the horn, and a meansfor superimposing a direct current signal on the induction coil so thatthe ultrasonic horn moves to a position within the chamber to modify theflow rate of the pressurized liquid.

The method includes the step of exciting the ultrasonic horn while theexit orifice receives pressurized liquid from the chamber, withoutapplying ultrasonic energy to the die tip, to modify the flow rate ofpressurized liquid through the exit orifice.

The method further includes the step of superimposing a direct currentsignal on the induction coil so that the ultrasonic horn moves to aposition within the chamber to shut-off the flow rate of the pressurizedliquid and removing the direct current signal on the induction coil sothat the ultrasonic horn moves to a position within the chamber to turnon the flow of the pressurized liquid.

The present invention is further described by the examples which follow.Such examples, however, are not to be construed as limiting in any wayeither the spirit or the scope of the present invention.

EXAMPLES

Ultrasonic Horn Apparatus

The following is a description of an exemplary ultrasonic horn apparatusof the present invention generally as shown in FIG. 1.

With reference to FIG. 1, the die housing 102 of the apparatus was acylinder having an outer diameter of 1.375 inches (about 34.9 mm), aninner diameter of 0.875 inch (about 22.2 mm), and a length of 3.086inches (about 78.4 mm). The outer 0.312-inch (about 7.9-mm) portion ofthe second end 108 of the die housing was threaded with 16-pitchthreads. The inside of the second end had a beveled edge 126, orchamfer, extending from the face 128 of the second end toward the firstend 106 a distance of 0.125 inch (about 3.2 mm). The chamfer reduced theinner diameter of the die housing at the face of the second end to 0.75inch (about 19.0 mm). An inlet 110 (also called an inlet orifice) wasdrilled in the die housing, the center of which was 0.688 inch (about17.5 mm) from the first end, and tapped. The inner wall of the diehousing consisted of a cylindrical portion 130 and a conical frustrumportion 132. The cylindrical portion extended from the chamfer at thesecond end toward the first end to within 0.992 inch (about 25.2 mm)from the face of the first end. The conical frustrum portion extendedfrom the cylindrical portion a distance of 0.625 inch (about 15.9 mm),terminating at a threaded opening 134 in the first end. The diameter ofthe threaded opening was 0.375 inch (about 9.5 mm); such opening was0.367 inch (about 9.3 mm) in length.

A die tip 136 was located in the threaded opening of the first end. Thedie tip consisted of a threaded cylinder 138 having a circular shoulderportion 140. The shoulder portion was 0.125 inch (about 3.2 mm) thickand had two parallel faces (not shown) 0.5 inch (about 12.7 mm) apart.An exit orifice 112 (also called an extrusion orifice) was drilled inthe shoulder portion and extended toward the threaded portion a distanceof 0.087 inch (about 2.2 mm). The diameter of the extrusion orifice was0.0145 inch (about 0.37 mm). The extrusion orifice terminated within thedie tip at a vestibular portion 142 having a diameter of 0.125 inch(about 3.2 mm) and a conical frustrum portion 144 which joined thevestibular portion with the extrusion orifice. The wall of the conicalfrustrum portion was at an angle of 30° from the vertical. Thevestibular portion extended from the extrusion orifice to the end of thethreaded portion of the die tip, thereby connecting the chamber definedby the die housing with the extrusion orifice.

The means for applying ultrasonic energy was a cylindrical ultrasonichorn 116. The horn was machined to resonate at a frequency of 20 kHz.The horn had a length of 5.198 inches (about 132.0 mm), which was equalto one-half of the resonating wavelength, and a diameter of 0.75 inch(about 19.0 mm). The face 146 of the first end 118 of the horn wasdrilled and tapped for a 3/8-inch (about 9.5-mm) stud (not shown). Thehorn was machined with a collar 148 at the nodal point 122. The collarwas 0.094-inch (about 2.4-mm) wide and extended outwardly from thecylindrical surface of the horn 0.062 inch (about 1.6 mm). Thus, thediameter of the horn at the collar was 0.875 inch (about 22.2 mm). Thesecond end 120 of the horn terminated in a small cylindrical tip 1500.125 inch (about 3.2 mm) long and 0.125 inch (about 3.2 mm) indiameter. Such tip was separated from the cylindrical body of the hornby a parabolic frustrum portion 152 approximately 0.5 inch (about 13 mm)in length. That is, the curve of this frustrum portion as seen incross-section was parabolic in shape. The face of the small cylindricaltip was normal to the cylindrical wall of the horn and was located about0.4 inch (about 10 mm) from the extrusion orifice. Thus, the face of thetip of the horn, i.e., the second end of the horn, was locatedimmediately above the vestibular opening in the threaded end of the dietip.

The first end 108 of the die housing was sealed by a threaded cap 154which also served to hold the ultrasonic horn in place. The threadsextended upwardly toward the top of the cap a distance of 0.312 inch(about 7.9 mm). The outside diameter of the cap was 2.00 inches (about50.8 mm) and the length or thickness of the cap was 0.531 inch (about13.5 mm). The opening in the cap was sized to accommodate the horn; thatis, the opening had a diameter of 0.75 inch (about 19.0 mm). The edge ofthe opening in the cap was a chamfer 156 which was the mirror image ofthe chamfer at the second end of the die housing. The thickness of thecap at the chamfer was 0.125 inch (about 3.2 mm), which left a spacebetween the end of the threads and the bottom of the chamfer of 0.094inch (about 2.4 mm), which space was the same as the length of thecollar on the horn. The diameter of such space was 1.104 inch (about28.0 mm). The top 158 of the cap had drilled in it four 1/4-inchdiameter×1/4-inch deep holes (not shown) at 90° intervals to accommodatea pin spanner. Thus, the collar of the horn was compressed between thetwo chamfers upon tightening the cap, thereby sealing the chamberdefined by the die housing.

A Branson elongated aluminum waveguide having an input:output mechanicalexcitation ratio of 1:1.5 was coupled to the ultrasonic horn by means ofa 3/8-inch (about 9.5-mm) stud. To the elongated waveguide was coupled apiezoelectric transducer, a Branson Model 502 Converter, which waspowered by a Branson Model 1120 Power Supply operating at 20 kHz(Branson Sonic Power Company, Danbury, Conn.). Power consumption wasmonitored with a Branson Model A410A Wattmeter.

Example 1

This example illustrates the present invention as it relates toregulating the flow of a variety of liquids through an orifice utilizingthe 20 kHz ultrasonic device (immersed horn) described above. Thefollowing liquids were used:

Non-toxic Food Grade H-1 Gear Oil 90 from Bel-Ray Company, Farmingdale,N.J. Viscosity=416 cP measured with a Brooksfield Model DV-II viscometerfor a 2 mL sample at 25° C. and a (#CP-41) 3.0° core spindle cone.

EP Hydraulic Oil 32 from Motor Oil, Inc., Elk Grove Village, Ill.Viscosity=43.2 cP measured with a Brooksfield Model DV-II viscometer fora 2 mL sample at 25° C. and a (#CP-41) 3.0° core spindle cone.

EP Hydraulic Oil 68 from Motor Oil, Inc., Elk Grove Village, Ill.Viscosity=106.8 cP measured with a Brooksfield Model DV-II viscometerfor a 2 mL sample at 25° C. and a (#CP-41) 3.0° core spindle cone.

Flow rate trials were conducted on the immersed horn with the varioustips without ultrasonic energy, with applied ultrasonic energy at 20% ofavailable power as indicated by the Branson power controller, and withapplied ultrasonic energy at 30% of available power as indicated by theBranson power controller. Results of the trials are reported in Tables1-3.

                  TABLE 1    ______________________________________    90 Weight Food Grade Gear Oil    No Ultrasound                 20% Ultrasound                               30% Ultrasound    Press.  Flow     Flow     Change Flow   Change    (PSI)   (g/min)  (g/min)  (%)    (g/min)                                            (%)    ______________________________________    Capillary Tip 0.0145" diameter × 0.087" length    150     29.36    95.72    326.02 99.28  338.15    200     65.16    92.56    142.05 95.88  147.15    280     80.35    86.50    107.65 101.10 125.82    Capillary Tip 0.010" diameter × 0.020" length    150     23.48    49.40    210.39 58.52  249.23    200     37.32    54.44    145.87 59.80  160.24    280     52.64    66.48    126.29 82.16  156.08    ______________________________________

                  TABLE 2    ______________________________________    EP Hydraulic Oil 32    No Ultrasound                 20% Ultrasound                               30% Ultrasound    Press.  Flow     Flow     Change Flow   Change    (PSI)   (g/min)  (g/min)  (%)    (g/min)                                            (%)    ______________________________________    Capillary Tip 0.006" diameter × 0.006" length    200     42.92    31.52    73.44  31.88  74.28    300     53.84    38.60    71.69  39.84  74.00    400     61.04    46.32    75.88  45.16  73.98    500     69.56    50.80    73.03  51.56  74.12    600     75.72    55.16    72.85  55.40  73.16    700     77.32    60.12    77.75  57.92  74.91    Capillary Tip 0.006" diameter × 0.010" length    200     29.80    25.80    86.58  25.48  85.50    300     42.44    35.00    82.47  34.32  80.87    400     51.36    40.24    78.35  39.20  76.32    500     60.24    44.80    74.37  44.08  73.17    600     67.28    47.96    71.28  49.44  73.48    700     74.64    60.84    81.51  55.52  74.38    Capillary Tip 0.004" diameter × 0.006" length    200     18.04    20.56    113.97 22.88  126.83    300     31.60    27.28    86.33  27.72  87.72    400     37.72    30.88    81.87  32.76  86.85    500     45.28    37.16    82.07  37.40  82.60    600     48.16    41.72    86.63  88.56  183.89    ______________________________________

                  TABLE 3    ______________________________________    EP Hydraulic Oil 68    No Ultrasound                 20% Ultrasound                               30% Ultrasound    Press.  Flow     Flow     Change Flow   Change    (PSI)   (g/min)  (g/min)  (%)    (g/min)                                            (%)    ______________________________________    Capillary Tip 0.010" diameter × 0.010" length    200     84.48    80.24    94.98  88.32  104.55    300     123.04   99.00    80.46  95.15  77.33    400     122.00   103.75   85.04  102.10 83.69    500     149.30   125.65   84.16  123.80 82.92    600     157.30   124.75   79.31  125.50 79.78    Capillary Tip 0.010" diameter × 0.020" length    200     52.76    71.96    136.39 69.24  131.24    300     90.48    91.68    101.33 96.48  106.63    400     96.35    94.95    98.55  95.95  99.58    500     128.35   107.60   83.83  107.55 83.79    600     145.60   116.95   80.32  121.80 83.65    700     156.20   157.50   100.83 136.75 87.55    Capillary Tip 0.006" diameter × 0.006" length    200     33.48    28.48    85.07  28.16  84.11    300     46.28    34.84    75.28  35.24  76.15    400     45.32    38.56    85.08  35.36  78.02    500     54.80    41.68    76.06  43.12  78.69    600     63.20    47.76    75.57  48.24  76.33    700     69.32    62.16    89.67  55.72  80.38    Capillary Tip 0.006" diameter × 0.010" length    200     18.04    22.88    126.83 25.56  141.69    300     36.00    31.76    88.22  33.56  93.22    400     45.00    36.12    80.27  37.12  82.49    500     52.56    43.16    82.12  43.52  82.80    600     55.52    47.32    85.23  48.44  87.25    700     70.12    63.88    91.10  49.28  70.28    Capillary Tip 0.004" diameter × 0.006" length    200     24.64    34.32    139.29 34.00  137.99    300     30.88    53.64    173.70 57.40  185.88    400     38.88    28.64    73.66  30.60  78.70    500     41.08    32.88    80.04  31.92  77.70    600     46.64    33.04    70.84  33.76  72.38    700     48.20    35.60    73.86  57.36  119.00    Capillary Tip 0.004" diameter × 0.004" length    200     6.92     17.64    254.91 16.48  238.15    300     14.52    17.28    119.01 16.04  110.47    400     18.84    19.32    102.55 20.28  107.64    500     26.20    21.76    83.05  22.32  85.19    600     18.88    21.24    112.50 19.52  103.39    700     33.08    29.40    88.88  31.36  94.80    800     48.28    44.44    92.05  50.60  104.81    ______________________________________

Example 2

This example illustrates the present invention as it relates toregulating the flow of a variety of liquids through an orifice utilizinga 40 kHz ultrasonic device (immersed horn). The device was set up in thesame configuration as the previous example. The ultrasonic horn and thechamber into which the horn fit were exactly one-half the length of the20 kHz.

The liquids used in this example were identical to those used in Example1 with the following exception:

Lubricating Oil 100 from Motor Oil, Inc., Elk Grove Village, Ill.Viscosity=163 cP measured with a Brooksfield Model DV-II viscometer fora 2 mL sample at 25° C. (#CP-41) 3.0° core spindle cone.

Flow rate trials were conducted on the immersed horn with the varioustips without ultrasonic energy, with applied ultrasonic energy at 20% ofavailable power as indicated by the Branson power controller, and withapplied ultrasonic energy at various wattages as indicated by theBranson power controller. Results of the trials are reported in Tables4-7.

                                      TABLE 4    __________________________________________________________________________    90 Weight Food Grade Gear Oil    Capillary Tip 0.010" diameter × 0.010" length    PRESS         POWER              TEMP RATE POWER                             TEMP RATE CHANGE    psi  watts              F.   g/min                        watts                             F.   g/min                                       %    __________________________________________________________________________    150  0    72   20.13                        80   80   45.52                                       226.1    200  0    72   29.54                        80   90   61.82                                       209.3    240  0    72   36.44                        80   92   69.03                                       189.4    280  0    72   45.20                        60   85   77.64                                       171.8    __________________________________________________________________________

                                      TABLE 5    __________________________________________________________________________    Lubricating Oil 100    Capillary Tip 0.010" diameter × 0.010" length    PRESS         POWER              TEMP RATE POWER                             TEMP RATE CHANGE    psi  watts              F.   g/min                        watts                             F.   g/min                                       %    __________________________________________________________________________    150  0    75   39.44                        85   85   54.78                                       138.9    200  0    75   56.01                        85   90   62.79                                       112.1    240  0    75   62.49                        80   85   68.91                                       110.3    280  0    75   76.98                        75   85   74.91                                        97.3    __________________________________________________________________________

                                      TABLE 6    __________________________________________________________________________    EP Hydraulic Oil 68    Capillary Tip 0.010" diameter × 0.010" length    PRESS         POWER              TEMP RATE POWER                             TEMP RATE CHANGE    psi  watts              F.   g/min                        watts                             F.   g/min                                       %    __________________________________________________________________________    150  0    72   59.28                        80   74    76.08                                       128.3    200  0    72   73.11                        80   76    96.69                                       132.3    240  0    72   82.83                        60   77   103.14                                       124.5    280  0    72   99.99                        75   78   111.72                                       111.7    __________________________________________________________________________

                  TABLE 7    ______________________________________    EP Hydraulic Oil 32    Capillary Tip 0.010" diameter × 0.010" length          POW-                  POW-  TE-  RA-   CHA-    PRESS ER      TEMP    RATE  ER    MP   TE    NGE    psi   watts   F.      g/min watts F.   g/min %    ______________________________________    150   0       72      71.60 130   77   90.48 126.4    200   0       72      95.60 170   77   114.42                                                 119.7    240   0       72      107.64                                170   77   117.54                                                 109.2    280   0       72      121.98                                170   77   133.56                                                 109.5    ______________________________________

Example 3

This example illustrates the present invention as it relates tostability of pressurized liquid upon extended exposure to 40 kHzultrasonic energy as the liquid cycled through a system.

Referring now to FIG. 2, there is shown an illustration of an exemplarysystem for cycling pressurized liquid through the ultrasonic controlapparatus. A storage unit 202 held approximately 1.5 gallons of liquidwhich was connected to a pump 204 (Dayton Capacitor Start Motor ModelNo. 2190453 from Dayton Electric Manufacturing Company, Chicago, Ill.).The oil flowed into a pressure controller 206 and to a pressure gauge208. The pump 204 was a constant pressure pump, thus a recycle stream210 controlled the pressure of flow of the liquid carried to theultrasonic apparatus 212. The ultrasonic apparatus 212 was set up in thesame configuration as described at the beginning of the Examples sectionwith the exception that the device operated at a frequency of 40 kHz.The ultrasonic horn and the chamber into which the horn fit were exactlyone-half the length of the 20 kHz horn described at the beginning of theExamples section. The exit orifice of the ultrasonic apparatus 212 wasdirected to a defoamer 214. Air entrained in the liquid exiting theorifice formed foam which was converted back into liquid in thedefoamer.

Approximately 420.5 grams of EP Hydraulic Oil 68 was run through thesystem at a rate of 109.6 grams per minute under a pressure of 200 psifor 480+ cycles.

Lubricating Oil 100 was run through the system at a rate of 24.8 gramsper minute at pressure of 200 psi for 300+ cycles.

A sample of each liquid was taken prior to the test. After each test,the samples were analyzed utilizing gel permeation chromatography (GPC)and infrared spectroscopy (IR). FIG. 3 is an overlay of the GPC analysisof the EP Hydraulic Oil 68 before and after 480 cycles. FIG. 4 is anoverlay of the GPC analysis of the Lubricating Oil 100 before and after300 cycles. FIG. 5 is the IR analysis of the control EP Hydraulic Oil68. FIG. 6 is the IR analysis of the EP Hydraulic Oil 68 after 480cycles. FIG. 7 is the IR analysis of the control Lubricating Oil 100.FIG. 8 is the IR analysis of the Lubricating Oil 100 after 300 cycles.Essentially no degradation of the oils can be detected.

Example 4

This example illustrates the present invention as it relates tostability of pressurized liquid upon extended exposure to 20 kHzultrasonic energy as the liquid cycled through a system.

Referring now to FIG. 9, there is shown an illustration of an exemplarysystem for cycling pressurized liquid through the ultrasonic controlapparatus. A pump 300 was connected to a pressure gauge 302. The pump300 was a Dayton DC Gear Motor Model No. 42128A regulated by a DaytonSCR Control, both available from Dayton Electric Manufacturing Company,Chicago, Ill. Because the pump could be regulated, it was possible tocontrol the flow rate and pressure by controlling the pump speed. Theliquid flowed to a pressure gauge 304. A recycle stream 306 was used tomaintain flow control. From the pressure gauge 304, the liquid flowed tothe ultrasonic apparatus 308. The ultrasonic apparatus 308 was set up inthe same configuration as described at the beginning of the Examplessection and was operated at 20 kHz. The exit orifice of the ultrasonicapparatus 308 was directed to a funnel (not shown). Liquid was allowedto fill the funnel above the plane of the exit orifice so the liquid wasnot exposed to air.

Approximately 52 grams of EP Hydraulic Oil 32 was run through the systemat a rate of 87.2 grams per minute under a pressure of 200+ psi for 600+cycles.

Approximately 54 grams of Lubricating Oil 100 was run through the systemat a rate of 91.4 grams per minute at pressure of 200+ psi for 800+cycles.

Approximately 51 grams of EP Hydraulic Oil 68 was run through the systemat a rate of 131.2 grams per minute under a pressure of 200+ psi for800+ cycles.

A sample of each liquid was taken prior to the test. After each test,the samples were analyzed utilizing gel permeation chromatography (GPC)and infrared spectroscopy (IR). FIG. 10 is an overlay of the GPCanalysis of the EP Hydraulic Oil 32 before and after 600 cycles. FIG. 11is an overlay of the GPC analysis of the Lubricating Oil 100 before andafter 800 cycles. FIG. 12 is an overlay of the GPC analysis of the EPHydraulic Oil 68 before and after 800 cycles. FIG. 13 is the IR analysisof the control EP Hydraulic Oil 32. FIG. 14 is the IR analysis of the EPHydraulic Oil 32 after 600 cycles. FIG. 15 is the IR analysis of theLubricating Oil 100 after 800 cycles. FIG. 16 is the IR analysis of theEP Hydraulic Oil 32 after 800 cycles. Essentially no degradation of theoils can be detected.

Related Applications

This application is one of a group of commonly assigned patentapplications which are being filed on the same date. The group includesapplication Ser. No. 08/576,543 entitled "An Apparatus And Method ForEmulsifying A Pressurized Multi-Component Liquid", Docket No. 12535, inthe name of L. K. Jameson et al.; application Ser. No. 08/576,536entitled "An Apparatus And Method For Ultrasonically Producing A SprayOf Liquid", Docket No. 12536, in the name of L. H. Gipson et al.;application Ser. No. 08/576,522 entitled "Ultrasonic Fuel InjectionMethod And Apparatus", Docket No. 12537, in the name of L. H. Gipson etal.; application Ser. No. 08/576,174, now U.S. Pat. No. 5,803,106,entitled "An Ultrasonic Apparatus And Method For Increasing The FlowRate Of A Liquid Through An Orifice", Docket No. 12538, in the name ofB. Cohen et al.; and application Ser. No. 08/576,175 entitled"Ultrasonic Flow Control Apparatus And Method", Docket No. 12539, in thename of B. Cohen et al. The subject matter of these applications ishereby incorporated by reference.

While the specification has been described in detail with respect tospecific embodiments thereof, it will be appreciated that those skilledin the art, upon attaining an understanding of the foregoing, mayreadily conceive of alterations to, variations of, and equivalents tothese embodiments. Accordingly, the scope of the present inventionshould be assessed as that of the appended claims and any equivalentsthereto.

What is claimed is:
 1. An ultrasonic apparatus for regulating the flowof pressurized liquid through an orifice, the apparatus comprising:a diehousing defining:a chamber adapted to receive a pressurized liquid; aninlet in communication with said chamber and adapted to supply thechamber with the pressurized liquid; and an exit orifice incommunication with said chamber and defined by the walls of a die tip,the exit orifice being adapted to receive the pressurized liquid fromthe chamber and pass the liquid out of the die housing; and a means forapplying ultrasonic energy to a portion of the pressurized liquid withinthe chamber without applying ultrasonic energy to the die tip, whereinthe means for applying ultrasonic energy is located within the chamber,and wherein the flow rate of the pressurized liquid through the exitorifice is modified when ultrasonic energy is applied to be at leastabout 25 percent greater than the flow rate of an identical pressurizedliquid out of an identical die housing through an identical exit orificein the absence of excitation by ultrasonic energy.
 2. The apparatus ofclaim 1, wherein the means for applying ultrasonic energy is an immersedultrasonic horn.
 3. The apparatus of claim 1, wherein the means forapplying ultrasonic energy is an immersed magnetostrictive ultrasonichorn.
 4. The apparatus of claim 1, wherein the exit orifice is aplurality of exit orifices.
 5. The apparatus of claim 1, wherein theexit orifice is a single exit orifice.
 6. The apparatus of claim 1,wherein the exit orifice has a diameter of from about 0.0001 to about0.1 inch.
 7. The apparatus of claim 6, wherein the exit orifice has adiameter of from about 0.001 to about 0.01 inch.
 8. The apparatus ofclaim 1, wherein the exit orifice is an exit capillary.
 9. The apparatusof claim 8, wherein the exit capillary has a length to diameter ratio offrom about 4:1 to about 10:1.
 10. The apparatus of claim 1, wherein theultrasonic energy has a frequency of from about 15 kHz to about 500 kHz.11. An ultrasonic apparatus for regulating the flow of pressurizedliquid through an orifice, the apparatus comprising:a die housing havinga first end and a second end and defining:a chamber adapted to receive apressurized liquid; an inlet in communication with said chamber andadapted to supply the chamber with the pressurized liquid; and an exitorifice in communication with said chamber and defined by the walls of adie tip, the exit orifice being located in the first end of the diehousing and adapted to receive the pressurized liquid from the chamberand pass the liquid out of the die housing along a first axis; and anultrasonic horn having a first end and a second end and adapted, uponexcitation by ultrasonic energy, to have a node and a longitudinalmechanical excitation axis, the horn being located in the second end ofthe die housing in a manner such that the first end of the horn islocated outside the die housing and the second end of the horn islocated inside the die housing, within the chamber, and is in closeproximity to the exit orifice but does not apply ultrasonic energy tothe die tip, wherein the flow rate of the pressurized liquid through theexit orifice is modified when ultrasonic energy is applied to be atleast about 25 percent greater than the flow rate of an identicalpressurized liquid out of an identical die housing through an identicalexit orifice in the absence of excitation bv ultrasonic energy.
 12. Theapparatus of claim 11, wherein the ultrasonic energy has a frequency offrom about 15 kHz to about 500 kHz.
 13. The apparatus of claim 11,wherein the longitudinal mechanical excitation axis is substantiallyparallel with the first axis.
 14. The apparatus of claim 11, wherein thesecond end of the ultrasonic horn has a cross-sectional areaapproximately the same as or less than a minimum area which encompassesall exit orifices in the die housing.
 15. The apparatus of claim 11,wherein the ultrasonic horn has coupled to the first end thereof avibrator means as a source of longitudinal mechanical excitation. 16.The apparatus of claim 15, wherein the vibrator means is a piezoelectrictransducer.
 17. The apparatus of claim 16, wherein the piezoelectrictransducer is coupled to the ultrasonic horn by means of an elongatedwaveguide.
 18. The apparatus of claim 17, wherein the elongatedwaveguide has an input: output mechanical excitation ratio of from about1:1 to about 1:2.5.
 19. The apparatus of claim 11, wherein theultrasonic horn is an immersed magnetostrictive ultrasonic horn.
 20. Amethod of regulating the flow of pressurized liquid through an orifice,the method comprising:supplying a pressurized liquid to a die assembly,the die assembly being composed of:a die housing comprising:a chamberadapted to receive a pressurized liquid; an inlet in communication withsaid chamber and adapted to supply the chamber with the pressurizedliquid; and an exit orifice in communication with said chamber anddefined by the walls of a die tip, the exit orifice being adapted toreceive the pressurized liquid from the chamber and pass the liquid outof the die housing; and a means for applying ultrasonic energy to aportion of the pressurized liquid within the chamber; exciting the meansfor applying ultrasonic energy with ultrasonic energy while the exitorifice receives pressurized liquid from the chamber, without applyingultrasonic energy to the die tip, to modify the flow rate of pressurizedliquid through the exit orifice so that it is at least about 25 percentgreater than the flow rate of an identical pressurized liquid out of anidentical die housing through an identical exit orifice in the absenceof excitation by ultrasonic energy; and passing the pressurized liquidout of the exit orifice in the die tip at the modified flow rate. 21.The method of claim 20 wherein the means for applying ultrasonic energyis located within the chamber.
 22. The method of claim 20, wherein themeans for applying ultrasonic energy is an immersed ultrasonic horn. 23.The method of claim 20, wherein the exit orifice is an exit capillary.24. The method of claim 20, wherein the ultrasonic energy has afrequency of from about 15 kHz to about 500 kHz.
 25. The method of claim20, wherein the ultrasonic energy has a frequency of from about 15 kHzto about 60 kHz.
 26. The method of claim 20, wherein the flow rate ofthe pressurized liquid is at least about 75 percent greater than theflow rate of an identical pressurized liquid out of an identical diehousing through an identical exit orifice in the absence of excitationby ultrasonic energy.
 27. The method of claim 20, wherein the flow rateof the pressurized liquid is at least about 200 percent greater than theflow rate of an identical pressurized liquid out of an identical diehousing through an identical exit orifice in the absence of excitationby ultrasonic energy.
 28. The method of claim 20, wherein the increasein flow rate of the pressurized liquid is achieved in the absence ofsignificant elevation in the temperature of the pressurized liquid. 29.The method of claim 20, wherein the increase in flow rate of thepressurized liquid is achieved in the absence of significant elevationin the supplied pressure of the pressurized liquid.
 30. A method ofregulating the flow of pressurized liquid through an orifice, the methodcomprising:supplying a pressurized liquid to a die assembly composedof:a die housing comprising:a chamber adapted to receive a pressurizedliquid; the chamber having a first end and a second end; an inlet incommunication with said chamber and adapted to supply the chamber withthe pressurized liquid; and an exit orifice in communication with saidchamber and defined by walls in a die tip and located in the first endof the chamber and adapted to receive the pressurized liquid from thechamber and pass the liquid out of the die housing along a first axis;and an ultrasonic horn having a first end and a second end and adapted,upon excitation by ultrasonic energy, to have a node and a longitudinalmechanical excitation axis, the horn being located in the second end ofthe chamber in a manner such that the first end of the horn is locatedoutside of the chamber and the second end of the horn is located withinthe chamber and is in close proximity to the extrusion orifice; excitingthe ultrasonic horn with ultrasonic energy while the exit orificereceives pressurized liquid from the chamber and without applyingultrasonic energy to the die tip, to modify the flow rate of pressurizedliquid through the exit orifice so that it is at least about 25 percentgreater than the flow rate of an identical pressurized liquid out of anidentical die housing through an identical exit orifice in the absenceof excitation by ultrasonic energy; and passing the liquid out of theexit orifice in the die tip at the modified flow rate.
 31. The method ofclaim 30, wherein the exit orifice is an exit capillary.
 32. The methodof claim 30, wherein the ultrasonic energy has a frequency of from about15 kHz to about 500 kHz.
 33. An ultrasonic apparatus for regulating theflow of pressurized liquid through an orifice, the apparatuscomprising:a die housing defining:a chamber adapted to receive apressurized liquid; an inlet adapted to supply the chamber with thepressurized liquid; and an exit orifice defined by the walls of a dietip, the exit orifice being adapted to receive the pressurized liquidfrom the chamber and pass the liquid out of the die housing; and anultrasonic horn located within the chamber, the horn being composed of amagnetostrictive material and surrounded by an induction coil capable ofinducing a signal into the magnetostrictive material causing it tovibrate at ultrasonic frequencies to apply ultrasonic energy to aportion of the pressurized liquid within the chamber without applyingultrasonic energy to the die tip, means for superimposing a directcurrent signal on the induction coil so that the ultrasonic horn movesto a position within the chamber to shut-off the flow of the pressurizedliquid and so that the ultrasonic horn moves to a position to turn onthe liquid flow when the direct current signal is removed, wherein theflow rate of pressurized liquid through the exit orifice is modifiedwhen ultrasonic energy and direct current signal is applied and removed.34. A method of regulating the flow of pressurized liquid through anorifice, the method comprising:supplying a pressurized liquid to a dieassembly, the die assembly being composed of:a die housing comprising:achamber adapted to receive a pressurized liquid; an inlet adapted tosupply the chamber with the pressurized liquid; and an exit orificedefined by the walls of a die tip, the exit orifice being adapted toreceive the pressurized liquid from the chamber and pass the liquid outof the die housing; and an ultrasonic horn located within the chamber,the horn being composed of a magnetostrictive material and surrounded byan induction coil capable of inducing a signal into the magnetostrictivematerial causing it to vibrate at ultrasonic frequencies to applyultrasonic energy to a portion of the pressurized liquid within thechamber without applying ultrasonic energy to the die tip; and means forsuperimposing a direct current signal on the induction coil so that theultrasonic horn moves to a position within the chamber to shut-off theflow of the pressurized liquid and so that the ultrasonic horn moves toa position to turn on the liquid flow when the direct current signal isremoved, exciting the ultrasonic horn while the exit orifice receivespressurized liquid from the chamber, without applying ultrasonic energyto the die tip, to modify the flow rate of pressurized liquid throughthe exit orifice; and superimposing a direct current signal on theinduction coil so that the ultrasonic horn moves to a position withinthe chamber to shut-off the flow rate of the pressurized liquid andremoving the direct current signal on the induction coil so that theultrasonic horn moves to a position within the chamber to turn on theflow of the pressurized liquid.